Relativistic Tidal Disruption in Black Hole and Wormhole Backgrounds

TL;DR

This study uses relativistic simulations to compare stellar tidal disruption events near black holes and wormholes, revealing key differences in outcomes and potential observational signatures.

Contribution

It introduces a relativistic hydrodynamics simulation framework to distinguish black hole and wormhole tidal disruptions through detailed analysis.

Findings

Black holes cause greater tidal stripping than wormholes.

The critical impact parameter for full disruption is higher in wormholes.

Observable fallback rates differ between black hole and wormhole backgrounds.

Abstract

Black holes (BHs) and wormholes (WHs) are characterized by distinct spacetime geometries, whose differences become pronounced close to the central objects. A useful way to probe such differences is via the dynamics of stellar tidal disruption events in the regime of strong gravity. Here, using a general relativistic smoothed particle hydrodynamics code inspired from an algorithm developed by Liptai and Price, we perform a suite of numerical simulations of solar mass polytropic stars in the background of supermassive Schwarzschild BHs and similar mass exponential WHs. Important differences between the two geometries near the BH event horizon or the WH throat is provided by the distinct outcomes of such events. For a given impact parameter, BH backgrounds lead to greater tidal stripping compared to WHs ones and further, the critical impact parameter, beyond which the star undergoes full tidal disruption is higher for WH backgrounds compared to BHs. We further study the differences in observable peak fallback rates in the two backgrounds. We also provide a quantitative explanation for the tendency of stars in partial tidal disruptions to retain larger cores around more massive centers, by computing tidal stresses in a Fermi normal coordinate system and introducing an appropriate measure of stellar compactness. Finally, we suggest a way to observationally distinguish BH and WH backgrounds, based on the properties of different observables.